EP3529683B1 - Schubvektorisierte multikopter - Google Patents

Schubvektorisierte multikopter Download PDF

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Publication number
EP3529683B1
EP3529683B1 EP17863172.7A EP17863172A EP3529683B1 EP 3529683 B1 EP3529683 B1 EP 3529683B1 EP 17863172 A EP17863172 A EP 17863172A EP 3529683 B1 EP3529683 B1 EP 3529683B1
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European Patent Office
Prior art keywords
thruster
control
axis
multicopter
variables
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EP17863172.7A
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English (en)
French (fr)
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EP3529683A1 (de
EP3529683A4 (de
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Sui Yang KHOO
Michael John NORTON
Abbas Zahedi KOUZANI
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Deakin University
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Deakin University
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    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D1/00—Control of position, course or altitude of land, water, air, or space vehicles, e.g. automatic pilot
    • G05D1/08—Control of attitude, i.e. control of roll, pitch, or yaw
    • G05D1/0808—Control of attitude, i.e. control of roll, pitch, or yaw specially adapted for aircraft
    • G05D1/0858—Control of attitude, i.e. control of roll, pitch, or yaw specially adapted for aircraft specially adapted for vertical take-off of aircraft
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C27/00—Rotorcraft; Rotors peculiar thereto
    • B64C27/04—Helicopters
    • B64C27/08—Helicopters with two or more rotors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C27/00—Rotorcraft; Rotors peculiar thereto
    • B64C27/20—Rotorcraft characterised by having shrouded rotors, e.g. flying platforms
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C27/00—Rotorcraft; Rotors peculiar thereto
    • B64C27/52—Tilting of rotor bodily relative to fuselage
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C39/00—Aircraft not otherwise provided for
    • B64C39/02—Aircraft not otherwise provided for characterised by special use
    • B64C39/024—Aircraft not otherwise provided for characterised by special use of the remote controlled vehicle type, i.e. RPV
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U50/00—Propulsion; Power supply
    • B64U50/10—Propulsion
    • B64U50/13—Propulsion using external fans or propellers
    • B64U50/14—Propulsion using external fans or propellers ducted or shrouded
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B13/00—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion
    • G05B13/02—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric
    • G05B13/04—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D1/00—Control of position, course or altitude of land, water, air, or space vehicles, e.g. automatic pilot
    • G05D1/0088—Control of position, course or altitude of land, water, air, or space vehicles, e.g. automatic pilot characterized by the autonomous decision making process, e.g. artificial intelligence, predefined behaviours
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D1/00—Control of position, course or altitude of land, water, air, or space vehicles, e.g. automatic pilot
    • G05D1/08—Control of attitude, i.e. control of roll, pitch, or yaw
    • G05D1/0808—Control of attitude, i.e. control of roll, pitch, or yaw specially adapted for aircraft
    • G05D1/0816—Control of attitude, i.e. control of roll, pitch, or yaw specially adapted for aircraft to ensure stability
    • G05D1/0825—Control of attitude, i.e. control of roll, pitch, or yaw specially adapted for aircraft to ensure stability using mathematical models
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U10/00—Type of UAV
    • B64U10/10—Rotorcrafts
    • B64U10/13—Flying platforms
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
    • B64U10/00—Type of UAV
    • B64U10/10—Rotorcrafts
    • B64U10/13—Flying platforms
    • B64U10/14—Flying platforms with four distinct rotor axes, e.g. quadcopters

Definitions

  • the present invention relates to aircraft having multiple thrust vectoring or tilting thrusters, and computer-implemented control systems for controlling such aircraft.
  • Unmanned aerial vehicles or aerial drones are increasingly being used for a wide variety of important commercial applications, such as aerial surveying or inspection of utility or infrastructure assets.
  • Conventional UAVs with fixed propulsion systems are flown by tilting along the desired direction of motion, in order to generate the necessary acceleration towards that direction.
  • tilting the entire UAV disadvantageously tilts any cameras, sensors and other equipment mounted on the fuselage of the UAV, which affects the quality, stability and accuracy of the data obtained from these sensors.
  • Thrust vectoring UAVs that are capable of vertical take-off and landing (VTOL) exhibit the advantages of both fixed-wing and rotary-wing aircraft. This is particularly useful for unmanned aerial vehicles (UAV) used in surveillance or reconnaissance, as this improves manoeuvrability during take-off and landing within constricted spaces, while still allowing for superior speed and altitude in flight compared to helicopters, for example.
  • UAV unmanned aerial vehicles
  • providing thrusters or propulsion units which are controllable and movable independently from the fuselage improves the positional stability of the fuselage, and therefore the quality of images, videos or data captured by equipment mounted on the fuselage. Further, independently thrust vectored propulsion improves the overall stability of the aircraft in response to environmental factors such as wind gusts.
  • a single-axis, single-gimbal tilt rotor with a PID controller is disclosed in RYLL MARKUS ET AL: "A Novel Overactuated Quadrotor Unmanned Aerial Vehicle: Modeling, Control, and Experimental Validation", IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY, vol. 23, no. 2, 1 March 2015 (2015-03-01), pages 540-556 .
  • AMIRI ET AL "Modelling of Opposed Lateral and Longitudinal Tilting Dual-Fan Unmanned Aerial Vehicle",IFAC THE 2012 IFAC WORKSHOP ON AUTOMATIC CONTROL IN OFFSHORE OIL AND GAS PRODUCTION, vol. 44, no. 1, 2 September 2011 (2011-09-02), pages 2054-2059,Red Hook, NY .
  • a method of operating a multicopter comprising a body and n thrusters, each thruster independently actuated to vector thrust angularly relative to the body about at least a first axis, the method comprising:
  • the thruster control variables are independently adjustable to control thrust amplitude and orientation of each thruster about the first axis.
  • Each thruster is further independently operable to vector thrust angularly relative to the body about a second axis orthogonal to the first axis, and wherein the thruster control variables are further independently adjustable to control orientation of each thruster about the second axis.
  • the model is decoupled by differentiating with respect to time, such that the thruster control variables comprise first derivatives of a) angular velocity of each thruster, b) orientation of each thruster about its first axis and c) orientation of each thruster about its second axis, and the method further comprises a step of integrating the new thruster control variables with respect to time to obtain values of thrust amplitude and orientation for actuating each thruster.
  • Each thruster is pivotably mounted to the body via two concentrically and orthogonally arranged gimbals configured to rotate the thruster about the first axis and second axis respectively, each gimbal being independently rotatable relative to the body via a worm gear, and wherein the method comprises actuating each worm gear according to the computed thruster control variables.
  • the control algorithm may be a robust control algorithm configured to account for system uncertainties and/or environmental disturbances.
  • the robust control algorithm may comprise multiple-surface sliding control.
  • an unmanned aerial vehicle system comprising:
  • Each thruster is further independently operable to vector thrust angularly relative to the body about a second axis orthogonal to the first axis.
  • the decoupled mathematical model is obtained by differentiating with respect to time an initial model of multicoptor dynamics comprising coupled, non-linear combinations of thruster variables, such that the decomposed model comprises linear combinations of first derivatives of a) angular velocity of each thruster, b) orientation of each thruster about its first axis and c) orientation of each thruster about its second axis.
  • Each thruster is pivotably mounted to the body via two concentrically and orthogonally arranged gimbals configured to rotate the thruster about the first axis and second axis respectively.
  • Each gimbal is independently rotatable relative to the body via a worm gear.
  • Each worm gear may be actuated by a servomotor.
  • the multicopter may be a quadcopter.
  • the control algorithm may be a robust control algorithm configured to account for system uncertainties and/or environmental disturbances.
  • the robust control algorithm may comprise multiple-surface sliding control.
  • a computer program product stored on a non-transitory tangible computer readable medium and comprising instructions that, when executed, cause the computer system to perform the method of paragraph 7
  • FIG. 1 shows a schematic view of an unmanned aerial vehicle (UAV) 1 according to one embodiment of the invention.
  • the UAV 1 is a quadcopter comprising a body 5 and four thrusters 10a, 10b, 10c, 10d mounted to the body.
  • the thrusters 10 may comprise rotors, propellers, ducted fans, or any other suitable propulsion means.
  • Each thruster 10 is independently operable to vector thrust angularly relative to the body 5 about two axes 15, 20.
  • the thruster 10 is rotatable relative to the body about a first axis 15 which is parallel to the longitudinal axis of arm 30 connecting thruster 10 to body 5.
  • Thruster 10 is also rotatable relative to the body about a second axis 20 perpendicular to first axis 15.
  • Axis 25 denotes the thruster's thrust force axis.
  • thrusters 10a, 10b, 10c, 10d are located at approximately the same distance from the centre of gravity of the UAV 1, and are arranged in approximate rotational symmetry about the centre of gravity.
  • the mathematical model and control algorithm of the present invention are designed to handle asymmetries of the UAV via the inertial term, described in more detail below.
  • each thruster 10 may be vectored relative to the body 5 about only a single axis. Accordingly, for each thruster 10, at least two variables are controlled independently of the other thrusters, ie the thrust amplitude and the angle of rotation of the thruster 10 relative to the body 5 about one axis. In preferred embodiments, as shown in Figure 1 , each thruster 10 may also be vectored about a second axis, introducing a third control variable that is the angle of rotation of each thruster relative to the body 5 of the UAV about the second axis. In other embodiments, the individual thrusters 10 may be grouped together and visualised as a single thruster that has orthogonally arranged gimbals configured as described in this paragraph and hereafter.
  • the thruster 10 comprises a ducted fan 80 pivotably mounted to arm 30 via two concentric, orthogonally arranged gimbal rings 60, 70.
  • the outer gimbal 60 is configured to rotate the ducted fan 80 about first axis 15 and the inner gimbal 70 is configured to rotate the ducted fan 80 about the second axis 20.
  • Each gimbal 60, 70 may be independently rotatable relative to the body 5 via a worm gear arrangement. That is, the outer gimbal 60 may be rotatable via worm 62 and worm gear 66, and the inner gimbal 70 may be rotatable via worm 72 and worm gear 76.
  • the worm gear arrangement allows the ducted fan 80 to be rotated with precision to any desired angle, so that the thruster 10 is capable of handling high thrust whilst accurately maintaining the desired orientation.
  • the worm gear arrangements may each be actuated by servomotors 64, 74, or any other suitable actuators. As shown in Figure 4 , the worm gear arrangements on the outer and inner gimbals may be mounted and protected within gear housing 68, 78 respectively.
  • the worm gear design advantageously provides for full directional control of the thruster about the entire range of gimbal motion while maintaining high accuracy and high torque. Further, the worm gear arrangement allows for self-locking, such that the position of the ducted fan 80 may be maintained without requiring additional power, thus improving efficiency while reducing the size of the motor required.
  • flight control unit 50 is programmed to receive and compare target flight performance (eg via user input) with data from sensors 35 positioned on the UAV.
  • the flight control unit 50 then outputs control signals to the thruster actuators 55(which may comprise thruster motors 85 and gimbal motors 64, 74) that control the thrust force and/or thrust vector of each thruster 10, in order to minimise the difference or error between the target values and the measured data according to the control algorithm.
  • Target flight performance input into control unit 50 may be high level targets such as target position, orientation, velocity, acceleration, etc of the UAV. This may be input by a user to the control unit 50, eg in real time, wirelessly, etc.
  • the target flight performance criteria may additionally or alternatively be pre-set, eg to follow a predetermined route.
  • Sensors 35 capture data relevant to the flight performance of the UAV, for example position, orientation, pitch, roll, velocity, angular velocity, etc.
  • the sensors 35 may comprise altimeters, gyroscopes, magnetometers, cameras, accelerometers, Global Positioning System (GPS) receivers, proximity sensors, inertial measurement units (IMU) or combinations thereof.
  • the sensors 35 may be located on the body 5 of the UAV and/or on the thrusters 10. Sensors on the thrusters may additionally or alternatively capture data relating to operation of each thruster, for example, position or angle of the thruster 10 relative to the body 5 of the UAV, angular velocity of associated fans, propellers or rotors, voltage, current, power, motor torque, or combinations thereof.
  • Data from the sensors 35 is transmitted to control unit 50.
  • Data from the sensors 35 may additionally be transmitted, eg via the control unit 50, to the user or pilot of the UAV.
  • Control unit 50 may be mounted on a support frame 8 of the body 5 of the UAV.
  • Power source 90 for supplying power to the thruster motors 85, gimbal motors 64, 74, sensors 35, control unit 50, etc, may also be mounted on the support frame 8.
  • the UAV may have legs 32 configured to elevate the body 5 and thrusters 10 above the ground.
  • FIG. 5 is a flowchart of a method 100 for controlling a multicopter 1 according to an embodiment of the invention.
  • the method 100 starts at operation 110 by receiving target input values from the UAV pilot, eg via command signals transmitted wirelessly in real time.
  • sensed data is received from sensors 35.
  • the target values are compared with sensed data to determine the error.
  • the control unit 50 computes, according to the control algorithm based on a decoupled UAV dynamics model, the thruster control variables required for minimising the error.
  • the computed control variables are input to the thruster actuators (eg thruster motors 85 and gimbal motors 64, 74).
  • the flight characteristics are sensed by sensors 35, to be fed back to the control unit 50 at operation 120.
  • embodiments of the present invention comprise overactuated systems.
  • each thruster 10 is independently vectored or tilted along two axes
  • eight additional control inputs are included in the system (in addition to the four conventional thrust amplitude variables), to control the UAV which has six degrees of freedom (DoF), ie translation and rotation in three spatial dimensions.
  • DoF degrees of freedom
  • prior art systems utilising linear control algorithms eg using PIDs, cannot provide optimal stability control of thrust vectored UAVs, even with careful tuning.
  • the control algorithm of the present invention utilises a technique for modelling the dynamics of overactuated, thrust vectored UAV systems, which allows for each thruster variable to be independently controlled.
  • the UAV 1 may have any number of thrusters 10.
  • the mathematical model and control algorithm of the present invention are readily extendable to handle any number of thrusters.
  • the UAV 1 is modelled with the body 5 and each thruster 10 treated as rigid bodies immersed in a fluid.
  • G is the robot's center of mass, m its mass, and J its inertia matrix.
  • B ⁇ O B ; X B ; Y B ; Z B ⁇ refers to the reference frame attached to the body 5 of the UAV and
  • the first axis of rotation 15 of the thruster refers to X Pi
  • the second axis of rotation 20 refers to Y Pi
  • the thruster thrust force axis 25 refers to Z Pi
  • ⁇ i represent each thruster's orientation or tilting angle with respect to axes 15 ( X Pi ) ⁇ i and 20 ( Y Pi ) respectively .
  • ⁇ B ⁇ R 3 is the angular velocity of the UAV body 5, expressed in the body reference frame, B .
  • ⁇ Pi ⁇ R 3 is the angular velocity of the i th thruster expressed in the propeller reference frame P i .
  • R 2 1 is the notation used for the rotation matrix representing the orientation of frame 2 with respect to frame 1 .
  • the relative motion of each thruster 10 may be linked to the body reference frame.
  • R X ⁇ : 1 0 0 0 cos ⁇ ⁇ sin ⁇ 0 sin ⁇ cos ⁇ , and represent the standard rotational matrix with respect to roll, pitch, and yaw of the frame respectively.
  • T Pi the applied torque acting on the i th propeller
  • I Pi is the inertia matrix of the i th propeller
  • ⁇ Piz is the third component of vector ⁇ Pi
  • k c > 0 is the coefficient of proportionality between ⁇ Piz and the counter-rotating torque about the Z Pi axis due to air drag
  • ⁇ i is the angular velocity of the i th propeller.
  • B subsystems S 1 and S 2 , describing the angular acceleration and position of the multicopter respectively, are derived as: where I B is the inertial matrix of the body 5 of the UAV and F D is the drag force on the UAV.
  • the inertial matrix I B may be used to account for asymmetries in the UAV, so that the subsystems S 1 and S 2 may be extended to describe the dynamics of asymmetrical or unbalanced UAVs.
  • subsystem S 4 In applications where the sensor 35 for capturing position of the UAV is a GPS sensor which references the world inertial reference frame W , a body to world rotation matrix R B W may be applied to subsystem S 4 : where vector ⁇ is the UAV's position in frame W . Similarly, using azimuth, roll and pitch angles, subsystem S 4 can be described in North east down (NED) coordinates.
  • NED North east down
  • subsystems S 1 , S 2 , S 3 , and S 4 are defined in terms of highly coupled, non-linear combinations of thruster control variables ⁇ i , ⁇ i and ⁇ P i . That is, the equations describing the dynamics of the multicopter, when arranged in terms of ⁇ Pi , include sines and cosines of ⁇ i and ⁇ i embedded in non-linear functions such that no unique solution for ⁇ i or ⁇ i can be directly computed for a given position or angular velocity of the multicopter.
  • the model may be decoupled by differentiating with respect to time. This results in a model comprising linear combinations of new thruster control variables ⁇ i , ⁇ i and ⁇ P i . That is, the model in equation (7) can be decomposed as: where
  • the control variables may accordingly be individually adjusted in accordance with any arbitrary control algorithm selected for the system. For example, sensed position and velocity of the multicopter may be input into the control system together with target position and velocity values. The control algorithm then outputs the required individual adjustments to the new thruster control variables, optionally integrating with respect to time to obtain real world values of ⁇ i , ⁇ i and ⁇ Pi , in order to converge the position and velocity of the multicopter to the target values.
  • the model may be decoupled via alternative techniques, eg by applying inequalities.
  • decoupling the model according to the present invention allows for optimal stability control, since the system is then characterised by the thruster variables individually and independently of each other.
  • the decoupled model may be used to design a robust control algorithm that takes into account system uncertainties such as noise, mismatched uncertainties, environmental and aerodynamic disturbances, etc.
  • a multiple-surface sliding control algorithm may be applied, for example according to the formulation discussed in Khoo, S., Man, Z. and Zhao, S. (2008) Automatica, 44(11), pp.2995-2998 .
  • x B [ X B Y B Z B ] T and T P
  • i [ 0 0 k c ⁇ P i Z
  • ⁇ ⁇ and ⁇ x B representing the external disturbances that affect the rate of change of the angular momentum and linear momentum of the UAV respectively.
  • the multiple-surface sliding control algorithm is effective in controlling the cascade system above to ensure system stability and good tracking performance even with the existence of external disturbances and system non-linearity.
  • Alternative control algorithms may be used, for example backstepping, Lyapunov, H-infinity control, sliding mode control, etc., optionally together with adaptive and/or intelligent control components such as adaptive control, fuzzy logic, neural networks, etc.
  • Embodiments of the invention provide aircraft, in particular UAV, having multiple thrusters that are each able to be independently and precisely vectored relative to the body or fuselage of the aircraft. This may improve manoeuvrability of the UAV, while maintaining the orientation and stability of the body 5, to thereby improve the performance of the UAV in various applications such as photography, tracking, surveillance, carrying of cargo, etc.
  • Embodiments of the invention additionally or alternatively provide methods for controlling thrust vectoring aircraft based on models of flight dynamics that are specifically modified to handle overactuation of the system resulting from the additional control variables associated with each thruster.
  • the decoupled models allow for independent control of each thruster variable, and may thus enable control algorithms to be designed for optimal stability control and/or robustness.

Claims (7)

  1. Verfahren zum Betreiben eines Multikopters (1), der einen Körper (5) und n > 2 Triebwerke umfasst, wobei jedes Triebwerk (10) unabhängig betätigt wird, um Schub relativ zu dem Körper um eine erste und eine zweite Achse (15, 20) abgewinkelt auszuüben, wobei das Verfahren Folgendes umfasst:
    Modellieren einer Dynamik des Multikopters mit einem mathematischen Modell, das gekoppelte, nichtlineare Kombinationen von Triebwerksvariablen umfasst;
    Entkoppeln des mathematischen Modells in lineare Kombinationen von Triebwerkssteuerungsvariablen,
    Erfassen wenigstens eines Merkmals der Multikopterdynamik;
    Vergleichen der erfassten Daten mit entsprechenden Zielmerkmalen;
    Berechnen von Einstellungen in Triebwerkssteuerungsvariablen zum Reduzieren der Differenz zwischen den erfassten Daten und den Zielmerkmalen gemäß einem Steuerungsalgorithmus; und
    Betätigen jedes Triebwerks gemäß den berechneten Triebwerkssteuerungsvariablen, um den Multikopter zu den Zielmerkmalen zu konvergieren;
    wobei der Steuerungsalgorithmus derart auf dem entkoppelten mathematischen Modell basiert, dass jede Triebwerkssteuerungsvariable unabhängig eingestellt werden kann,
    wobei die Triebwerkssteuerungsvariablen unabhängig voneinander einstellbar (i) sind, um eine Schubamplitude und eine Ausrichtung jedes Triebwerks um die erste Achse zu steuern;
    wobei jedes Triebwerk ferner unabhängig betreibbar ist, um Schub relativ zu dem Körper um eine zweite Achse orthogonal zu der ersten Achse abgewinkelt auszuüben;
    wobei die Triebwerkssteuerungsvariablen ferner unabhängig voneinander einstellbar sind, um die Ausrichtung jedes Triebwerks um die zweite Achse zu steuern;
    wobei das Modell durch Differenzieren hinsichtlich Zeit derart entkoppelt wird, dass die Triebwerkssteuerungsvariablen erste Ableitungen von a) Winkelgeschwindigkeit jedes Triebwerks, b) Ausrichtung jedes Triebwerks um seine erste Achse und c) Ausrichtung jedes Triebwerks um seine zweite Achse umfassen;
    wobei das Verfahren ferner einen Schritt eines Integrierens der neuen Triebwerkssteuerungsvariablen hinsichtlich Zeit umfasst, um Werte der Schubamplitude und Ausrichtung zum Betätigen jedes Triebwerks zu erhalten;
    wobei jedes Triebwerk an den Körper über zwei konzentrisch und orthogonal angeordnete kardanische Rahmen (60, 70), die konfiguriert sind, um das Triebwerk um die erste Achse beziehungsweise die zweite Achse zu drehen, schwenkbar montiert ist, wobei jeder kardanische Rahmen über ein Schneckenrad (66, 76) relativ zu dem Körper unabhängig drehbar ist und
    wobei jedes Schneckenrad gemäß den berechneten Triebwerkssteuerungsvariablen betätigt wird.
  2. Verfahren nach Anspruch 1, wobei der Steuerungsalgorithmus ein robuster Steuerungsalgorithmus ist, der konfiguriert ist, um Systemunsicherheiten und/oder Umgebungsstörungen zu berücksichtigen.
  3. Verfahren nach Anspruch 2, wobei der robuste Steuerungsalgorithmus eine Steuerung mehrerer Gleitflächen umfasst.
  4. Unbemanntes Luftfahrzeugsystem, das Folgendes umfasst:
    einen Multikopter, der n>2 Triebwerke aufweist, die an einem Körper montiert sind, wobei jedes Triebwerk unabhängig voneinander betätigbar ist, um Schub relativ zu dem Körper um eine erste Achse abgewinkelt auszuüben;
    wenigstens einen Sensor (35) an dem Multikopter zum Erfassen wenigstens eines Merkmals der Multikopterdynamik; und
    eine Steuerungseinheit (50), die konfiguriert ist, um die erfassten Daten zu empfangen und die erfassten Daten mit dem/den entsprechenden Zielmerkmal(en) zu vergleichen;
    wobei die Steuerungseinheit programmiert ist, um Änderungen in Triebwerkssteuerungsvariablen zu berechnen, die zum Reduzieren der Differenz zwischen den erfassten Daten und dem/den Zielmerkmal(en) gemäß einem Steuerungsalgorithmus erforderlich sind;
    wobei der Steuerungsalgorithmus auf einem entkoppelten mathematischen Modell der Multikopterdynamik basiert, wobei das entkoppelte Modell lineare Kombinationen von Triebwerkssteuerungsvariablen umfasst;
    wobei die Steuerungseinheit konfiguriert ist, um die berechnete(n) Änderung(en) als Steuerungssignale auszugeben, um jedes Triebwerk unabhängig zu betätigen;
    wobei jedes Triebwerk ferner unabhängig betreibbar ist, um Schub relativ zu dem Körper um eine zweite Achse orthogonal zu der ersten Achse abgewinkelt auszuüben;
    wobei das entkoppelte mathematische Modell durch Differenzieren hinsichtlich Zeit eines anfänglichen Modells von Multikopterdynamik erhalten wird, das gekoppelte, nichtlineare Kombinationen von Triebwerksvariablen umfasst, derart, dass das zerlegte Modell lineare Kombinationen erster Ableitungen von a) Winkelgeschwindigkeit jedes Triebwerks, b) Ausrichtung jedes Triebwerks um seine erste Achse und c) Ausrichtung jedes Triebwerks um seine zweite Achse umfasst;
    wobei jedes Triebwerk an den Körper über zwei konzentrisch und orthogonal angeordnete kardanische Rahmen, die konfiguriert sind, um das Triebwerk um die erste Achse beziehungsweise die zweite Achse zu drehen, schwenkbar montiert ist;
    wobei jeder kardanische Rahmen über ein Schneckenrad relativ zu dem Körper unabhängig drehbar ist.
  5. Unbemanntes Luftfahrzeugsystem nach Anspruch 4, wobei jedes Schneckenrad durch einen Servomotor (64, 74) betätigt wird.
  6. Unbemanntes Luftfahrzeugsystem nach Anspruch 5, wobei der Multikopter ein Quadrokopter ist.
  7. Computerprogrammprodukt, das auf einem nichtflüchtigen greifbaren computerlesbaren Medium gespeichert ist und Anweisungen umfasst, die, wenn sie ausgeführt werden, das Computersystem veranlassen, das Verfahren nach Anspruch 1 durchzuführen.
EP17863172.7A 2016-10-18 2017-10-18 Schubvektorisierte multikopter Active EP3529683B1 (de)

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AU2016904231A AU2016904231A0 (en) 2016-10-18 Thrust vectored multicopters
PCT/AU2017/051129 WO2018071970A1 (en) 2016-10-18 2017-10-18 Thrust vectored multicopters

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EP3529683A1 (de) 2019-08-28
US11199858B2 (en) 2021-12-14
US20190243385A1 (en) 2019-08-08
AU2017344750B2 (en) 2022-04-14
CA3040564A1 (en) 2018-04-26
EP3529683A4 (de) 2020-07-01
AU2017344750A1 (en) 2019-05-30

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